Typewriting machine



m. 24, 1939. H. J. HART TYPEWRITING MACHINE Filed Oct. 25, 1935 PatentedOct. 24, 1939 PATENT OFFICE TYPEWRITING MACHINE Henry J. Hart, WestHartford, Conn assi'gnor to Royal Typewriter Company, Inc., New York, N.Y., a corporation of New York Application October 25, 1935, Serial No.46,814

4 Claims,

This invention relates to new and useful improvements in typewritingmachines generally, although more particularly to abutments or anvilsforthe type bars.

The principal objects of the inventionare to provide an abutment whichwill reduce the noise made by a type bar connecting the same, and

- to provide means for easily assembling the abutment and the segmentguard plate on the segment, or removing the same therefrom.

With these and other objects in view which will more fully appear, thenature of the invention'will be more clearly understood by following thedescription, the appended .claims, and the several views illustratedinthe accompanying drawing.

In the drawing:

Figure 1 is a front elevation of a type bar segment'constructed inaccordance with my invention,

Figure 2 is a top plan View thereof,

Figure 3 is a perspective view of the segment,

Figure 4 is a perspective view of the abutment,

Figure 5 is a detail cross-sectional view taken on the line 5-5 ofFigure l, and v I Figure 6 is an enlarged cross sectional view of theabutment.

Referring to the accompanying drawing, the segment A is formed along itslower portion with the usual radially extending slots 5 for receivingthe heels of type bars 6 which are pivoted on the wire 1. The centralportion of the segment A above the type bar pivots is formed with anarcuate recess 8, and partially extending into this recess is a verticalweb or wall 9 which is spaced rearwardly from the front face of thesegment to form a resultant arouate seat I!) located directly above theslots 5, said seat including an arcuate groove l i formed in the frontface of the web 9 and an arcuate undercut or inclined lateral wall l2which is disposed directly in front of the web and merges with the loweredge of the groove ll. Attached to the rear face of the web it by screwsI3 is the usual sheet metal type bar 45 guide I4.

An arcuate abutment B of sound-deadening and wear-resisting constructionis received in the groove H of the seat Hi, the outer periphery [5 ofthe abutment being transversely inclined 5 to fit the inclined lateralwall [2 of the seat.

of the abutment. The depth of the groove II is equal to the'thickness ofthe rearmost plate l6, and integral with the next adjacent plate areinwardly extending attaching ears 18, It which lie flush against thefront face of the web 9. Screws l8; 19 pass through the ears I8, IBand'are engageable in threaded openings 29, 20 located in the web 9. Themost forwardly disposed plate It constitutes a front striker plate whoseouter face is disposed in advance of the front face of the segment so asto be engaged by the type bars when the latter are swung upwardly toprint, as shown in Figure 5.

It is well known that surfaces generally considered perfectly flat arenot perfect planes, and that when such surfaces are opposed one to theother air pockets intervene. It will be obvious therefore that when amultiplicity of thin spring steel plates are assembled face to face toform an abutment pack as shown in Figures 4 and 6 of the drawing,microscopic air pockets exist between the opposed surfaces of the platesand serve to deaden the sound of type bar impacts.

The equidistant spacing of the assembling rivets I! contributes to theuniformity of the relation between the respective plates l6 constitutingthe abutment pack. It will be noted also that the plate equipped withthe ears I8 constitutes a mounting plate and that the remainder of theplates are held on the mounting plate as and for the purposes stated.

A sheet metal guard plate 2! for the recess 8 is positioned against thefront face of the web 9 and overlies the ears l8 of the abutment B. Theplate is secured to the web by the screws I 9, the lower edge of theplate being arcuate and lying directly above and in abutting relation tothe upper arcuate surface of the abutment B.

From the foregoing, it will be seen that I have provided an abutment ofsound-deadening and wear-resisting construction; that the abutment canbe readily applied to or removed from the segment, and when in operativeposition the abutment is firmly seated throughout its entire length andconsequently the abutment will react uniformly to the impacts of all thetype bars.

I claim:

1. A self-contained laminated abutment for typewriter type bars adaptedto be attached as a unit to and detached as a unit from a type barsegment, said abutment comprising a plurality of fiat thin arcuatemetallic plates; means extending between the outermost plates andthrough the intermediate plates for securing said plates togetherirrespective of whether the abutment is attached to or detached from thesegment; and means for attaching the abutment to the segment.

2. In a typewriting' machine, the combination with type bars and asegment on which they are pivoted; of an assembled laminated abutmentfor said type bars adapted to be attached as a unit to said segment anddetached as unit from said segment, said abutment in itself comprising amultiplicity of laminae, a metal facing plate, a rear plate, connectingmeans extending between said facing plate and said rear plate andpassing through intervening laminae, said facing plate, rear plate, andconnecting means holding said laminae together, and there beingcushioning air films between the laminae; and means independent of saidconnecting means for detachably mounting said abutment as a unit on saidsegment.

3. In a typewriting machine, the combination with type bars and asegment on which they are pivoted; of an assembled laminated abutmentfor said type bars adapted to be attached as a unit to saidsegment anddetached as a unit from said segment, said abutment in itself comprisinga multiplicity of laminae, a metal facing plate, a

rear plate, rivets extending between said facing plate and said rearplate and passing through intervening laminae, said facing plate, rearplate, and rivets holding said laminae together, and there beingcushioning air films between the laminae; and. means independent of saidrivets for detachably mounting said abutment as a unit on said segment.

4. In a typewriting machine, the combination with type bars and asegment to which the type bars are pivoted, said segment above the typebar pivots being formed with a seat comprising an arcuate groove locatedin the front face of the segment and a forwardly disposed arcuatelateral wall merging with the lower edge of said groove, an arcuateabutment for the type bars mounted in said seat, said abutmentcomprising a laminated structure consisting of a plurality of metallicplates rigidly secured together, the depth of the groove being equal tothe thickness of the rearmost plate, attaching ears integral with thenext adjacent plate and extendinginwardly therefrom, and screws passingthrough the ears and having threadable engagement withthe segment. r

HENRY J. HART.

